Statistics

The mean of grouped data

The mean of grouped data is calculated using three methods: 1) Direct Method: x̄ = Σfᵢxᵢ/Σfᵢ where xᵢ is the class mark and fᵢ is the frequency. 2) As

Mode is the value that occurs

Mode is the value that occurs most frequently. For grouped data, we find the modal class (class with highest frequency) and use the formula: Mode = l

Median is the middle value when

Median is the middle value when data is arranged in order. For grouped data, we use cumulative frequency to find the median class (where n/2 lies) and

Cumulative frequency is the running total

Cumulative frequency is the running total of frequencies. It can be 'less than' type (frequencies of values less than upper class limits) or 'more tha

Class mark (or mid

Class mark (or mid-point) = (Upper limit + Lower limit)/2. It represents all values in that class interval. Class intervals group continuous data into